var big = document.querySelector('.big');
var topBig = document.querySelector('.top-big');
big.onmouseover = function() {
	topBig.style.display = 'block'
}


var rotate = document.querySelector('.rotate');
var rotateLi = document.querySelectorAll('.rotate li')
rotate.style.width=rotateLi.length*rotateLi[0].offsetWidth+'px';